The Norwegians are at the bottom of Group Nine with just three points from five games and victory for the Scots will finish any hopes Egil Olsen's side have of reaching South Africa next summer.
The Blackburn wideman is aware that only a Norwegian victory will do at the Ullevaal Stadium.
"It is like a cup final for us, we have to win and if we lose we are out," he said.
"I expected us to be higher up the table but we think we still have a decent chance.
"However, we have to win the game - we can't lose it.
"It's going to be a tough game because Scotland can't afford to lose either.
"Scotland have good players and I think they will sit back and play on the counter-attack but we will see."
While George Burley's players are in various stages of fitness, with some yet to play a competitive game, the Norwegian league season is up and running.
Pedersen hopes superior fitness in some areas of the pitch will give the home side an edge.
He said: "I have a good feeling about this game.
"The Norwegian league is under way and we have lots of good players in good shape.
"Hopefully we can get a little bit of an advantage from that.
"We should have had more points as I said but hopefully we can get the three points that we need to keep our dreams of getting to the World Cup alive."
Olsen admits his side will have to take risks against Scotland if they are to rescue their World Cup hopes.
Asked if he knew that victory was crucial for his side, Olsen, who took over his country for the second time in January after Age Hareide had quit, retorted: "Don't tell me - I know.
"We will try hard and that means we have to take risks, bigger risks than normal, because 0-0 is useless for us.
"Scotland have good players but they have lost some since they beat Iceland in the last game.
"I don't know how much weaker they are - but I hope they are very much weaker."